Catalysts for polyurethane foam polyol premixes containing halogenated olefin blowing agents

ABSTRACT

The invention provides polyurethane and polyisocyanurate foams and methods for the preparation thereof. More particularly, the invention relates to closed-celled, polyurethane and polyisocyanurate foams and methods for their preparation. The foams are characterized by a fine uniform cell structure and little or no foam collapse. The foams are produced with a polyol premix composition which comprises a combination of a hydrohaloolefin blowing agent, a polyol, a silicone surfactant, and a non-amine catalyst used alone or in combination with an amine catalyst.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/275,568, filed Feb. 14, 2019 (now pending), which is a continuationof U.S. application Ser. No. 15/843,684, filed Dec. 15, 2017 (nowabandoned), which is a continuation of U.S. application Ser. No.12/967,345, filed Dec. 14, 2010 (now abandoned), which in turn claimsthe priority benefit of U.S. provisional application No. 61/287,603filed Dec. 17, 2009, the contents of which are incorporated herein byreference.

FIELD OF THE INVENTION

The present invention pertains to polyurethane and polyisocyanuratefoams and methods for the preparation thereof.

BACKGROUND OF THE INVENTION

Low density, rigid to semi-rigid polyurethane or polyisocyanurate foamshave utility in a wide variety of insulation applications includingroofing systems, building panels, building envelope insulation, sprayapplied foams, one and two component froth foams, insulation forrefrigerators and freezers, and so called integral skin for applicationsuch as steering wheels and other automotive or aerospace cabin parts,shoe soles, and amusement park restraints. Critical to the large-scalecommercial acceptance of rigid polyurethane foams is their ability toprovide a good balance of properties. For example, rigid polyurethaneand polyisocyanurate foams are known to provide outstanding thermalinsulation, excellent fire resistance properties, and superiorstructural properties at reasonably low densities. Integral skin foamsare known to produce a tough durable outer skin and a cellular,cushioning core.

It is known in the art to produce rigid or semi-rigid polyurethane andpolyisocyanurate foams by reacting a polyisocyanate with one or morepolyols in the presence of one or more blowing agents, one or morecatalysts, one or more surfactants and optionally other ingredients.Blowing agents include hydrocarbons, fluorocarbons, chlorocarbons,chlorofluorocarbons, hydrochlorofluorocarbons, halogenated hydrocarbons,ethers, esters, aldehydes, alcohols, ketones, organic acid or gas, mostoften CO₂, generating materials. Heat is generated when thepolyisocyanate reacts with the polyol, and volatilizes the blowing agentcontained in the liquid mixture, thereby forming bubbles therein. In thecase of gas generating materials, gaseous species are generated bythermal decomposition or reaction with one or more of the ingredientsused to produce the polyurethane or polyisocyanurate foam. As thepolymerization reaction proceeds, the liquid mixture becomes a cellularsolid, entrapping the blowing agent in the foam's cells. If a surfactantis not used in the foaming composition, the bubbles simply pass throughthe liquid mixture without forming a foam or forming a foam with large,irregular cells rendering it not useful.

The foam industry has historically used liquid fluorocarbon blowingagents because of their ease of use and ability to produce foams withsuperior mechanical and thermal insulation properties. Fluorocarbons notonly act as blowing agents by virtue of their volatility, but also areencapsulated or entrained in the closed cell structure of the rigid foamand are the major contributor to the low thermal conductivity propertiesof the rigid urethane foams. Fluorocarbon-based blowing agents alsoproduce a foam having a favorable k-factor. The k-factor is the rate oftransfer of heat energy by conduction through one square foot ofone-inch thick homogenous material in one hour where there is adifference of one degree Fahrenheit perpendicularly across the twosurfaces of the material. Since the utility of closed-cellpolyurethane-type foams is based, in part, on their thermal insulationproperties, it would be advantageous to identify materials that producelower k-factor foams.

Preferred blowing agents also have low global warming potential. Amongthese are hydrohaloolefins including hydrofluoroolefins of whichtrans-1,3,3,3-tetrafluoropropene (1234ze(E)) and1,1,1,4,4,4hexafluorobut-2-ene (1336mzzm(Z)) are of particular interestand hydrochlorofluoroolefins of whichtrans-1-chloro-3,3,3-trifluoropropene (1233zd(E)) is of particularinterest. Processes for the manufacture oftrans-1,3,3,3-tetrafluoropropene are disclosed in U.S. Pat. Nos.7,230,146 and 7,189,884. Processes for the manufacture oftrans-1-chloro-3,3,3-trifluoropropene are disclosed in U.S. Pat. Nos.6,844,475 and 6,403,847.

It is convenient in many applications to provide the components forpolyurethane or polyisocyanurate foams in pre-blended formulations. Mosttypically, the foam formulation is pre-blended into two components. Thepolyisocyanate and optionally isocyanate compatible raw materials,including but not limited to certain blowing agents and non-reactivesurfactants, comprise the first component, commonly referred to as the“A” component. A polyol or mixture of polyols, one or more surfactant,one or more catalyst, one or more blowing agent, and other optionalcomponents including but not limited to flame retardants, colorants,compatibilizers, and solubilizers comprise the second component,commonly referred to as the “B” component. Accordingly, polyurethane orpolyisocyanurate foams are readily prepared by bringing together the Aand B side components either by hand mix for small preparations and,preferably, machine mix techniques to form blocks, slabs, laminates,pour-in-place panels and other items, spray applied foams, froths, andthe like. Optionally, other ingredients such as fire retardants,colorants, auxiliary blowing agents, and other polyols can be added tothe mixing head or reaction site. Most conveniently, however, they areall incorporated into one B component.

A shortcoming of two-component systems, especially those using certainhydrohaloolefins, including 1234ze(E), 1336(Z), and 1233zd(E), is theshelf-life of the B-side composition. Normally when a foam is producedby bringing together the A and B side components, a good foam isobtained. However, if the polyol premix composition is aged, prior totreatment with the polyisocyanate, the foams are of lower quality andmay even collapse during the formation of the foam.

SUMMARY OF THE INVENTION

It has now been found that the origin of the problem is the reaction ofcertain amine catalysts with certain hydrohaloolefins including 1234ze,1233zd, 1336mzzm, and/or combinations thereof. It has been found that,subsequent to the decomposition of the blowing agent, the molecularweight of the polymeric silicone surfactants, if present, isdetrimentally altered.

While it is possible to solve the problem by separating the blowingagent, surfactant, and catalyst, for example by adding the blowingagent, amine catalyst, or surfactant to the polyisocyanate, (“A”component) or by introducing the blowing agent, amine catalyst, orsurfactant using a separate stream from the “A” or “B” component, apreferred solution is one that does not require a change in the way thefoams are made. It has now been found that non-amine catalysts, e.g.inorgano-metallic catalysts, organo-metallic catalysts and/or quaternaryammonium carboxylate catalysts, either alone or in combination withamine catalysts, can extend the shelf life of polyol premixes containinghydrohaloolefins, such as, but not limited to 1234ze(E), 1233zd(E),and/or 1336mzzm(Z), such that good quality foams can be produced even ifthe polyol blend has been aged several weeks or months.

Accordingly, this invention relates to rigid to semi-rigid, polyurethaneand polyisocyanurate foams and methods for their preparation, whichfoams are characterized by a fine uniform cell structure and little orno foam collapse. The foams are produced with an organic polyisocyanateand a polyol premix composition which comprises a combination of ablowing agent, which is preferably a hydrohaloolefin, a polyol, asilicone surfactant, and a catalyst in which catalyst comprises one ormore non-amine catalyst, preferably an inorgano- or organo-metalliccompound or a quaternary ammonium carboxylate catalyst, and also mayinclude one or more amine catalysts.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides polyol premix composition which comprises acombination of a blowing agent, one or more polyols, one or moresilicone surfactants, and a catalyst in which catalyst is a non-aminecatalyst, such as an inorgano- or organo-metallic compound or quaternaryammonium carboxylate material used either alone or in combination withamine catalysts, wherein the blowing agent comprises one or morehydrohaloolefins, and optionally a hydrocarbon, fluorocarbon,chlorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, halogenatedhydrocarbon, ether, ester, alcohol, aldehyde, ketone, organic acid, gasgenerating material, water or combinations thereof.

The invention also provides a method of preparing a polyurethane orpolyisocyanurate foam comprising reacting an organic polyisocyanate withthe polyol premix composition.

The blowing agent component comprises a hydrohaloolefin, preferablycomprising at least one or a combination of 1234ze(E), 1233zd(E), and/or1336mzzm(Z), and optionally a hydrocarbon, fluorocarbon, chlorocarbon,fluorochlorocarbon, halogenated hydrocarbon, ether, fluorinated ether,ester, alcohol, aldehyde, ketone, organic acid, gas generating material,water or combinations thereof.

The hydrohaloolefin preferably comprises at least one halooalkene suchas a fluoroalkene or chlorofluoroalkene containing from 3 to 4 carbonatoms and at least one carbon-carbon double bond. Preferredhydrohaloolefins non-exclusively include trifluoropropenes,tetrafluoropropenes such as (1234), pentafluoropropenes such as (1225),chlorotrifloropropenes such as (1233), chlorodifluoropropenes,chlorotrifluoropropenes, chlorotetrafluoropropenes, hexafluorobutenes(1336) and combinations of these. More preferred that the compounds ofthe present invention are the tetrafluoropropene, pentafluoropropene,and chlorotrifloropropene compounds in which the unsaturated terminalcarbon has not more than one F or Cl substituent. Included are1,3,3,3-tetrafluoropropene (1234ze); 1,1,3,3-tetrafluoropropene;1,2,3,3,3-pentafluoropropene (1225ye), 1,1,1-trifluoropropene;1,2,3,3,3-pentafluoropropene, 1,1,1,3,3-pentafluoropropene (1225zc) and1,1,2,3,3-pentafluoropropene (1225yc); (Z)-1,1,1,2,3-pentafluoropropene(1225yez); 1-chloro-3,3,3-trifluoropropene (1233zd),1,1,1,4,4,4-hexafluorobut-2-ene (1336mzzm) or combinations thereof, andany and all stereoisomers of each of these.

Preferred hydrohaloolefins have a Global Warming Potential (GWP) of notgreater than 150, more preferably not greater than 100 and even morepreferably not greater than 75. As used herein, “GWP” is measuredrelative to that of carbon dioxide and over a 100-year time horizon, asdefined in “The Scientific Assessment of Ozone Depletion, 2002, a reportof the World Meteorological Association's Global Ozone Research andMonitoring Project,” which is incorporated herein by reference.Preferred hydrohaloolefins also preferably have an Ozone DepletionPotential (ODP) of not greater than 0.05, more preferably not greaterthan 0.02 and even more preferably about zero. As used herein, “ODP” isas defined in “The Scientific Assessment of Ozone Depletion, 2002, Areport of the World Meteorological Association's Global Ozone Researchand Monitoring Project,” which is incorporated herein by reference.

Preferred optional co-blowing agents non-exclusively include water,organic acids that produce CO₂ and/or CO, hydrocarbons; ethers,halogenated ethers; esters, alcohols, aldehydes, ketones,pentafluorobutane; pentafluoropropane; hexafluoropropane;heptafluoropropane; trans-1,2 dichloroethylene; methylal, methylformate; 1-chloro-1,2,2,2-tetrafluoroethane (124);1,1-dichloro-1-fluoroethane (141b); 1,1,1,2-tetrafluoroethane (134a);1,1,2,2-tetrafluoroethane (134); 1-chloro 1,1-difluoroethane (142b);1,1,1,3,3-pentafluorobutane (365mfc); 1,1,1,2,3,3,3-heptafluoropropane(227ea); trichlorofluoromethane (11); dichlorodifluoromethane (12);dichlorofluoromethane (22); 1,1,1,3,3,3-hexafluoropropane (236fa);1,1,1,2,3,3-hexafluoropropane (236ea); 1,1,1,2,3,3,3-heptafluoropropane(227ea), difluoromethane (32); 1,1-difluoroethane (152a);1,1,1,3,3-pentafluoropropane (245fa); butane; isobutane; normal pentane;isopentane; cyclopentane, or combinations thereof. In certainembodiments the co-blowing agent(s) include one or a combination ofwater and/or normal pentane, isopentane or cyclopentane, which may beprovided with one or a combination of the hydrohaloolefin blowing agentsdiscussed herein. The blowing agent component is usually present in thepolyol premix composition in an amount of from about 1 wt. % to about 30wt. %, preferably from about 3 wt. % to about 25 wt. %, and morepreferably from about 5 wt. % to about 25 wt. %, by weight of the polyolpremix composition. When both a hydrohaloolefin and an optional blowingagent are present, the hydrohaloolefin component is usually present inthe blowing agent component in an amount of from about 5 wt. % to about90 wt. %, preferably from about 7 wt. % to about 80 wt. %, and morepreferably from about 10 wt. % to about 70 wt. %, by weight of theblowing agent component; and the optional blowing agent is usuallypresent in the blowing agent component in an amount of from about 95 wt.% to about 10 wt. %, preferably from about 93 wt. % to about 20 wt. %,and more preferably from about 90 wt. % to about 30 wt. %, by weight ofthe blowing agent component.

The polyol component, which includes mixtures of polyols, can be anypolyol which reacts in a known fashion with an isocyanate in preparing apolyurethane or polyisocyanurate foam. Useful polyols comprise one ormore of a sucrose containing polyol; phenol, a phenol formaldehydecontaining polyol; a glucose containing polyol; a sorbitol containingpolyol; a methylglucoside containing polyol; an aromatic polyesterpolyol; glycerol; ethylene glycol; diethylene glycol; propylene glycol;graft copolymers of polyether polyols with a vinyl polymer; a copolymerof a polyether polyol with a polyurea; one or more of (a) condensed withone or more of (b), wherein (a) is selected from glycerine, ethyleneglycol, diethylene glycol, trimethylolpropane, ethylene diamine,pentaerythritol, soy oil, lecithin, tall oil, palm oil, and castor oil;and (b) is selected from ethylene oxide, propylene oxide, a mixture ofethylene oxide and propylene oxide; and combinations thereof. The polyolcomponent is usually present in the polyol premix composition in anamount of from about 60 wt. % to about 95 wt. %, preferably from about65 wt. % to about 95 wt. %, and more preferably from about 70 wt. % toabout 90 wt. %, by weight of the polyol premix composition.

The polyol premix composition next contains a silicone surfactant. Thesilicone surfactant is used to form a foam from the mixture, as well asto control the size of the bubbles of the foam so that a foam of adesired cell structure is obtained. Preferably, a foam with smallbubbles or cells therein of uniform size is desired since it has themost desirable physical properties such as compressive strength andthermal conductivity. Also, it is critical to have a foam with stablecells which do not collapse prior to forming or during foam rise.

Silicone surfactants for use in the preparation of polyurethane orpolyisocyanurate foams are available under a number of trade names knownto those skilled in this art. Such materials have been found to beapplicable over a wide range of formulations allowing uniform cellformation and maximum gas entrapment to achieve very low density foamstructures. The preferred silicone surfactant comprises a polysiloxanepolyoxyalkylene block co-polymer. Some representative siliconesurfactants useful for this invention are Momentive's L-5130, L-5180,L-5340, L-5440, L-6100, L-6900, L-6980 and L-6988; Air Products DC-193,DC-197, DC-5582, and DC-5598; and B-8404, B-8407, B-8409 and B-8462 fromEvonik Industries AG of Essen, Germany. Others are disclosed in U.S.Pat. Nos. 2,834,748; 2,917,480; 2,846,458 and 4,147,847. The siliconesurfactant component is usually present in the polyol premix compositionin an amount of from about 0.5 wt. % to about 5.0 wt. %, preferably fromabout 1.0 wt. % to about 4.0 wt. %, and more preferably from about 1.5wt. % to about 3.0 wt. %, by weight of the polyol premix composition.

The polyol premix composition may optionally contain a non-siliconesurfactant, such as a non-silicone, non-ionic surfactant. Such mayinclude oxyethylated alkylphenols, oxyethylated fatty alcohols, paraffinoils, castor oil esters, ricinoleic acid esters, turkey red oil,groundnut oil, paraffins, and fatty alcohols. A preferred non-siliconenon-ionic surfactant is LK-443 which is commercially available from AirProducts Corporation. When a non-silicone, non-ionic surfactant used, itis usually present in the polyol premix composition in an amount of fromabout 0.25 wt. % to about 3.0 wt. %, preferably from about 0.5 wt. % toabout 2.5 wt. %, and more preferably from about 0.75 wt. % to about 2.0wt. %, by weight of the polyol premix composition.

The inventive polyol premix composition next contains a catalyst orcatalysts at least one of which is a non-amine catalyst. In oneembodiment, the non-amine catalysts are inorgano- or organo-metalliccompounds. Useful inorgano- or organo-metallic compounds include, butare not limited to, organic salts, Lewis acid halides, or the like, ofany metal, including, but not limited to, transition metals,post-transition (poor) metals, rare earth metals (e.g. lanthanides),metalloids, alkali metals, alkaline earth metals, or the like. Examplesof such metals may include, but are not limited to, bismuth, lead, tin,zinc, chromium, cobalt, copper, iron, manganese, magnesium, potassium,sodium, titanium, mercury, zinc, antimony, uranium, cadmium, thorium,aluminum, nickel, cerium, molybdenum, vanadium, zirconium, orcombinations thereof. Non-exclusive examples of such inorgano- ororgano-metallic catalysts include, but are not limited to, bismuthnitrate, lead 2-ethylhexoate, lead benzoate, lead naphthanate, ferricchloride, antimony trichloride, antimony glycolate, tin salts ofcarboxylic acids, dialkyl tin salts of carboxylic acids, potassiumacetate, potassium octoate, potassium 2-ethylhexoate, potassium salts ofcarboxylic acids, zinc salts of carboxylic acids, zinc 2-ethylhexanoate,glycine salts, alkali metal carboxylic acid salts, sodiumN-(2-hydroxy-5-nonylphenol)methyl-N-methylglycinate, tin (II)2-ethylhexanoate, dibutyltin dilaurate, or combinations thereof. Thesecatalysts are usually present in the polyol premix composition in anamount of from about 0.25 wt. % to about 3.0 wt. %, preferably fromabout 0.3 wt. % to about 2.5 wt. %, and more preferably from about 0.35wt. % to about 2.0 wt. %, by weight of the polyol premix composition.While these are usual amounts, the quantity amount of the foregoingcatalyst can vary widely, and the appropriate amount can be easily bedetermined by those skilled in the art.

In another embodiment of the invention, the non-amine catalyst is aquaternary ammonium carboxylate. Useful quaternary ammonium carboxylatesinclude, but are not limited to: (2-hydroxypropyl)trimethylammonium2-ethylhexanoate (TMR® sold by Air Products and Chemicals) and(2-hydroxypropyl)trimethylammonium formate (TMR-2® sold by Air Productsand Chemicals). These quaternary ammonium carboxylate catalysts areusually present in the polyol premix composition in an amount of fromabout 0.25 wt. % to about 3.0 wt. %, preferably from about 0.3 wt. % toabout 2.5 wt. %, and more preferably from about 0.35 wt. % to about 2.0wt. %, by weight of the polyol premix composition. While these are usualamounts, the quantity amount of catalyst can vary widely, and theappropriate amount can be easily be determined by those skilled in theart.

In another embodiment, the non-amine catalyst is used in combinationwith an amine catalyst. Such amine catalysts may include any compoundcontaining an amino group and exhibiting the catalytic activity providedherein. Such compounds may be straight chain or cyclic non-aromatic oraromatic in nature. Useful, non-limiting, amines include primary amines,secondary amines or tertiary amines. Useful tertiary amine catalystsnon-exclusively include N,N,N′,N″,N″-pentamethyldiethyltriamine,N,N-dicyclohexylmethylamine; N,N-ethyldiisopropylamine;N,N-dimethylcyclohexylamine; N,N-dimethylisopropylamine;N-methyl-N-isopropylbenzylamine; N-methyl-N-cyclopentylbenzylamine;N-isopropyl-N-sec-butyl-trifluoroethylamine;N,N-diethyl-(α-phenylethyl)amine, N,N,N-tri-n-propylamine, orcombinations thereof. Useful secondary amine catalysts non-exclusivelyinclude dicyclohexylamine; t-butylisopropylamine; di-t-butylamine;cyclohexyl-t-butylamine; di-sec-butylamine, dicyclopentylamine;di-(α-trifluoromethylethyl)amine; di-(α-phenylethyl)amine; orcombinations thereof. Useful primary amine catalysts non-exclusivelyinclude: triphenylmethylamine and 1,1-diethyl-n-propylamine.

Other useful amines includes morpholines, imidazoles, ether containingcompounds, and the like. These include:

dimorpholinodiethylether

N-ethylmorpholine N-methylmorpholine

bis(dimethylaminoethyl) etherimidizolen-methylimidazole1,2-dimethylimidazoledimorpholinodimethyletherN,N,N′,N′,N″,N″-pentamethyldiethylenetriamineN,N,N′,N′,N″,N″-pentaethyldiethylenetriamineN,N,N′,N′,N″,N″-pentamethyldipropylenetriaminebis(diethylaminoethyl) etherbis(dimethylaminopropyl) ether.

In embodiments where an amine catalyst is provided, the catalyst may beprovided in any amount to achieve the function of the instant inventionwithout affecting the foam forming or storage stability of thecomposition, as characterized herein. To this end, the amine catalystmay be provided in amounts less than or greater than the non-aminecatalyst.

The preparation of polyurethane or polyisocyanurate foams using thecompositions described herein may follow any of the methods well knownin the art can be employed, see Saunders and Frisch, Volumes I and IIPolyurethanes Chemistry and technology, 1962, John Wiley and Sons, NewYork, N.Y. or Gum, Reese, Ulrich, Reaction Polymers, 1992, OxfordUniversity Press, New York, N.Y. or Klempner and Sendijarevic, PolymericFoams and Foam Technology, 2004, Hanser Gardner Publications,Cincinnati, Ohio. In general, polyurethane or polyisocyanurate foams areprepared by combining an isocyanate, the polyol premix composition, andother materials such as optional flame retardants, colorants, or otheradditives. These foams can be rigid, flexible, or semi-rigid, and canhave a closed cell structure, an open cell structure or a mixture ofopen and closed cells.

It is convenient in many applications to provide the components forpolyurethane or polyisocyanurate foams in pre-blended formulations. Mosttypically, the foam formulation is pre-blended into two components. Theisocyanate and optionally other isocyanate compatible raw materials,including but not limited to blowing agents and certain siliconesurfactants, comprise the first component, commonly referred to as the“A” component. The polyol mixture composition, including surfactant,catalysts, blowing agents, and optional other ingredients comprise thesecond component, commonly referred to as the “B” component. In anygiven application, the “B” component may not contain all the abovelisted components, for example some formulations omit the flameretardant if flame retardancy is not a required foam property.Accordingly, polyurethane or polyisocyanurate foams are readily preparedby bringing together the A and B side components either by hand mix forsmall preparations and, preferably, machine mix techniques to formblocks, slabs, laminates, pour-in-place panels and other items, sprayapplied foams, froths, and the like. Optionally, other ingredients suchas fire retardants, colorants, auxiliary blowing agents, water, and evenother polyols can be added as a stream to the mix head or reaction site.Most conveniently, however, they are all incorporated into one Bcomponent as described above.

A foamable composition suitable for forming a polyurethane orpolyisocyanurate foam may be formed by reacting an organicpolyisocyanate and the polyol premix composition described above. Anyorganic polyisocyanate can be employed in polyurethane orpolyisocyanurate foam synthesis inclusive of aliphatic and aromaticpolyisocyanates. Suitable organic polyisocyanates include aliphatic,cycloaliphatic, araliphatic, aromatic, and heterocyclic isocyanateswhich are well known in the field of polyurethane chemistry. These aredescribed in, for example, U.S. Pat. Nos. 4,868,224; 3,401,190;3,454,606; 3,277,138; 3,492,330; 3,001,973; 3,394,164; 3,124.605; and3,201,372. Preferred as a class are the aromatic polyisocyanates.

Representative organic polyisocyanates correspond to the formula:

R(NCO)z

wherein R is a polyvalent organic radical which is either aliphatic,aralkyl, aromatic or mixtures thereof, and z is an integer whichcorresponds to the valence of R and is at least two. Representative ofthe organic polyisocyanates contemplated herein includes, for example,the aromatic diisocyanates such as 2,4-toluene diisocyanate, 2,6-toluenediisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, crudetoluene diisocyanate, methylene diphenyl diisocyanate, crude methylenediphenyl diisocyanate and the like; the aromatic triisocyanates such as4,4′,4″-triphenylmethane triisocyanate, 2,4,6-toluene triisocyanates;the aromatic tetraisocyanates such as4,4′-dimethyldiphenylmethane-2,2′5,5-′tetraisocyanate, and the like;arylalkyl polyisocyanates such as xylylene diisocyanate; aliphaticpolyisocyanate such as hexamethylene-1,6-diisocyanate, lysinediisocyanate methylester and the like; and mixtures thereof. Otherorganic polyisocyanates include polymethylene polyphenylisocyanate,hydrogenated methylene diphenylisocyanate, m-phenylene diisocyanate,naphthylene-1,5-diisocyanate, 1-methoxyphenylene-2,4-diisocyanate,4,4′-biphenylene diisocyanate, 3,3′-dimethoxy-4,4′-biphenyldiisocyanate, 3,3′-dimethyl-4,4′-biphenyl diisocyanate, and3,3′-dimethyldiphenylmethane-4,4′-diisocyanate; Typical aliphaticpolyisocyanates are alkylene diisocyanates such as trimethylenediisocyanate, tetramethylene diisocyanate, and hexamethylenediisocyanate, isophorene diisocyanate, 4,4′-methylenebis(cyclohexylisocyanate), and the like; typical aromatic polyisocyanates include m-,and p-phenylene disocyanate, polymethylene polyphenyl isocyanate, 2,4-and 2,6-toluenediisocyanate, dianisidine diisocyanate, bitoyleneisocyanate, naphthylene 1,4-diisocyanate,bis(4-isocyanatophenyl)methene, bis(2-methyl-4-isocyanatophenyl)methane,and the like. Preferred polyisocyanates are the polymethylene polyphenylisocyanates, Particularly the mixtures containing from about 30 to about85 percent by weight of methylenebis(phenyl isocyanate) with theremainder of the mixture comprising the polymethylene polyphenylpolyisocyanates of functionality higher than 2. These polyisocyanatesare prepared by conventional methods known in the art. In the presentinvention, the polyisocyanate and the polyol are employed in amountswhich will yield an NCO/OH stoichiometric ratio in a range of from about0.9 to about 5.0. In the present invention, the NCO/OH equivalent ratiois, preferably, about 1.0 or more and about 3.0 or less, with the idealrange being from about 1.1 to about 2.5. Especially suitable organicpolyisocyanate include polymethylene polyphenyl isocyanate,methylenebis(phenyl isocyanate), toluene diisocyanates, or combinationsthereof.

In the preparation of polyisocyanurate foams, trimerization catalystsare used for the purpose of converting the blends in conjunction withexcess A component to polyisocyanurate-polyurethane foams. Thetrimerization catalysts employed can be any catalyst known to oneskilled in the art, including, but not limited to, glycine salts,tertiary amine trimerization catalysts, quaternary ammoniumcarboxylates, and alkali metal carboxylic acid salts and mixtures of thevarious types of catalysts. Preferred species within the classes arepotassium acetate, potassium octoate, and sodiumN-(2-hydroxy-5-nonylphenol)methyl-N-methylglycinate.

Conventional flame retardants can also be incorporated, preferably inamount of not more than about 20 percent by weight of the reactants.Optional flame retardants include tris(2-chloroethyl)phosphate,tris(2-chloropropyl)phosphate, tris(2,3-dibromopropyl)phosphate,tris(1,3-dichloropropyl)phosphate, tri(2-chloroisopropyl)phosphate,tricresyl phosphate, tri(2,2-dichloroisopropyl)phosphate, diethylN,N-bis(2-hydroxyethyl) aminomethylphosphonate, dimethylmethylphosphonate, tri(2,3-dibromopropyl)phosphate,tri(1,3-dichloropropyl)phosphate, and tetra-kis-(2-chloroethyl)ethylenediphosphate, triethylphosphate, diammonium phosphate, varioushalogenated aromatic compounds, antimony oxide, aluminum trihydrate,polyvinyl chloride, melamine, and the like. Other optional ingredientscan include from 0 to about 7 percent water, which chemically reactswith the isocyanate to produce carbon dioxide. This carbon dioxide actsas an auxiliary blowing agent. Formic acid is also used to producecarbon dioxide by reacting with the isocyanate and is optionally addedto the “B” component.

In addition to the previously described ingredients, other ingredientssuch as, dyes, fillers, pigments and the like can be included in thepreparation of the foams. Dispersing agents and cell stabilizers can beincorporated into the present blends. Conventional fillers for useherein include, for example, aluminum silicate, calcium silicate,magnesium silicate, calcium carbonate, barium sulfate, calcium sulfate,glass fibers, carbon black and silica. The filler, if used, is normallypresent in an amount by weight ranging from about 5 parts to 100 partsper 100 parts of polyol. A pigment which can be used herein can be anyconventional pigment such as titanium dioxide, zinc oxide, iron oxide,antimony oxide, chrome green, chrome yellow, iron blue siennas,molybdate oranges and organic pigments such as para reds, benzidineyellow, toluidine red, toners and phthalocyanines.

The polyurethane or polyisocyanurate foams produced can vary in densityfrom about 0.5 pounds per cubic foot to about 60 pounds per cubic foot,preferably from about 1.0 to 20.0 pounds per cubic foot, and mostpreferably from about 1.5 to 6.0 pounds per cubic foot. The densityobtained is a function of how much of the blowing agent or blowing agentmixture disclosed in this invention plus the amount of auxiliary blowingagent, such as water or other co-blowing agents is present in the Aand/or B components, or alternatively added at the time the foam isprepared. These foams can be rigid, flexible, or semi-rigid foams, andcan have a closed cell structure, an open cell structure or a mixture ofopen and closed cells. These foams are used in a variety of well knownapplications, including but not limited to thermal insulation,cushioning, flotation, packaging, adhesives, void filling, crafts anddecorative, and shock absorption.

The following non-limiting examples serve to illustrate the invention.

Example 1 (Comparative Example)

A polyol (B Component) formulation was made up of 100 parts by weight ofa polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.5parts by weight water, 1.2 parts by weight pentamethyldiethylenetriamine(sold as Polycat 5 by Air Products and Chemicals) catalyst, and 8 partsby weight trans-1,3,3,3-tetrafluoropropene blowing agent. The total Bcomponent composition, when freshly prepared and combined with 120.0parts by weight of Lupranate M20S polymeric isocyanate yielded a goodquality foam with a fine and regular cell structure. Foam reactivity wastypical for a pour in place foam. The total B-side composition (112.2parts) was then aged at 130° F. for 62 hours, and then combined with120.0 parts of M20S polymeric isocyanate to make a foam. The foam wasvery poor in appearance with significant cell collapse. Significantyellowing of the polyol premix was noted during aging.

Example 2 (Comparative Example)

A polyol (B Component) formulation was made up of 100 parts by weight ofa polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.5parts by weight water, 1.2 parts by weight pentamethyldiethylenetriamine(sold as Polycat 5 by Air Products and Chemicals) catalyst and 8 partsby weight blowing agent trans-1-chloro-3,3,3-trifluoropropene. The totalB component composition, when freshly prepared and combined with 120.0parts by weight of Lupranate M20S polymeric isocyanate yielded a goodquality foam with a fine and regular cell structure. Foam reactivity wastypical for a pour in place foam. The total B-side composition (112.2parts) was then aged at 130° F. for 168 hours, and then combined with120.0 parts of M20S polymeric isocyanate to make a foam. The foam wasvery poor in appearance with significant cell collapse. Significantyellowing of the polyol premix was noted during aging.

Example 3 (Foam Test)

A polyol (B Component) formulation was made up of 100 parts by weight ofa polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.5parts by weight water, 2.0 parts by weight N,N-dicyclohexylmethylamine(sold as Polycat 12 by Air Products and Chemicals) catalyst (a differentamine was used such that both this foam and the comparative example hadthe same initial reactivity), 1.75 parts by weight a bismuth basedcatalyst (sold as Dabco MB-20 by Air Products and Chemicals) and 8 partsby weight trans-1,3,3,3-tetrafluoropropene blowing agent. The total Bcomponent composition, when freshly prepared and combined with 120.0parts by weight of Lupranate M20S polymeric isocyanate yielded a goodquality foam with a fine and regular cell structure. Foam reactivity wastypical for a pour in place foam. The total B-side composition (114.75parts) was then aged at 130° F. for 336 hours, and then combined with120.0 parts of M20S polymeric isocyanate to make a foam. The foam wasexcellent in appearance with no evidence of cell collapse. There was noyellowing of the polyol premix noted during aging.

Example 4 (Foam Test)

A polyol (B Component) formulation was made up of 100 parts by weight ofa polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 0.5parts by weight water, 2.0 parts by weight N,N-dicyclohexylmethylamine(sold as Polycat 12 by Air Products and Chemicals) catalyst (a differentamine was used such that both this foam and the comparative example hadthe same initial reactivity), 1.75 parts by weight of zinc2-ethylhexanoate (sold as 30-3038 by Strem Chemicals) and 8 parts byweight trans-1-chloro-3,3,3-trifluoropropene blowing agent. The total Bcomponent composition, when freshly prepared and combined with 103.0parts by weight of Lupranate M20S polymeric isocyanate yielded a goodquality foam with a fine and regular cell structure. Foam reactivity wastypical for a pour in place foam. The total B-side composition (113.75parts) was then aged at 130° F. for 336 hours, and then combined with103.0 parts of M20S polymeric isocyanate to make a foam. The foam wasexcellent in appearance with no evidence of cell collapse. There was noyellowing of the polyol premix noted during aging

Example 5 (Foam Test)

A polyol (B Component) formulation was made up of 100 parts by weight ofa polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.0parts by weight water, 2.0 parts by weight N,N-dicyclohexylmethylamine(sold as Polycat 12 by Air Products and Chemicals) catalyst (a differentamine was used such that both this foam and the comparative example hadthe same initial reactivity), 1.75 parts by weight a Potassium basedcatalyst (sold as Dabco K15 by Air Products and Chemicals) and 8 partsby weight trans-1-chloro-3,3,3-trifluoropropene blowing agent. The totalB component composition, when freshly prepared and combined with 112.0parts by weight of Lupranate M20S polymeric isocyanate yielded a goodquality foam with a fine and regular cell structure. Foam reactivity wastypical for a pour in place foam. The total B-side composition (114.75parts) was then aged at 130° F. for 504 hours, and then combined with112.0 parts of M20S polymeric isocyanate to make a foam. The foam wasgood in appearance with only slight evidence of cell collapse. There wasvery slight yellowing of the polyol premix noted during aging.

What is claimed is:
 1. A stored foamable composition having storagestability comprising: a. from about 1 wt. % to about 30 wt. % of blowingagent, said blowing agent comprising from about 5 wt. % to about 90 wt %of trans-1,3,3,3-tetrafluoropropene and/ortrans-1-chloro-3,3,3-trifluoropropene, b. one or more polyols, c. one ormore surfactants, and d. a non-amine catalyst comprising anorganometallic compound wherein the organometallic compoundindependently comprises a carboxylate salt of a metal selected from thegroup consisting of bismuth, zinc, tin and combinations thereof, whereinsaid stored foamable composition has been stored for a period of atleast several weeks and is sufficiently stable to form foams with nosubstantial collapse after said period of storage.
 2. The foamablecomposition of claim 1 wherein said non-amine catalyst comprises zinc2-ethylhexanoate.
 3. The foamable composition of claim 2 wherein saidnon-amine catalyst is present in an amount of about 0.25 wt. % to about3.0 wt. %, by weight of the composition.
 4. The foamable composition ofclaim 1 wherein said blowing agent further comprises a co-blowing agentselected from the group consisting of water, hydrocarbon, fluorocarbon,chlorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, halogenatedhydrocarbon, ether, ester, alcohol, aldehyde, ketone, organic acid, gasgenerating material, and combinations thereof.
 5. The foamablecomposition of claim 1 further comprising an amine catalyst, providedsaid amine catalyst is present in an amount that does not negate thefoam forming ability of said foamable composition after said storageperiod.
 6. The foamable composition of claim 5 wherein the aminecatalyst is selected from the group consisting ofN,N,N′,N″,N″-pentamethyldiethyltriamine, N,N-dicyclohexylmethylamine;N,N-ethyldiisopropylamine; N,N-dimethylcyclohexylamine;N,N-dimethylisopropylamine; N-methyl-N-isopropylbenzylamine;N-methyl-N-cyclopentylbenzylamine;N-isopropyl-N-sec-butyl-trifluoroethylamine;N,N-diethyl-(α-phenylethyl)amine, N,N,N-tri-n-propylamine,dicyclohexylamine; t-butylisopropylamine; di-t-butylamine;cyclohexyl-t-butylamine; di-sec-butylamine, dicyclopentylamine;di-(α-trifluoromethylethyl)amine; di-(α-phenylethyl)amine;triphenylmethylamine; 1,1-diethyl-n-propylamine;dimorpholinodiethylether; N-ethylmorpholine; N-methylmorpholine;bis(dimethylaminoethyl) ether; imidizole; n-methylimidazole;1,2-dimethylimidazole; dimorpholinodimethylether;N,N,N′,N′,N″,N″-pentamethyldiethylenetriamine;N,N,N′,N′,N″,N″-pentaethyldiethylenetriamine;N,N,N′,N′,N″,N″-pentamethyldipropylenetriamine; bis(diethylaminoethyl)ether; bis(dimethylaminopropyl) ether; and combinations thereof.
 7. Astored polyol premix composition having storage stability comprising: a.from about 1 wt. % to about 30 wt. % of blowing agent, said blowingagent comprising from about 5 wt. % to about 90 wt % oftrans-1,3,3,3-tetrafluoropropene and/ortrans-1-chloro-3,3,3-trifluoropropene, b. one or more polyols, c. one ormore surfactants, and d. a non-amine catalyst comprising anorganometallic compound wherein the organometallic compound comprises acarboxylate salt of a metal selected from the group consisting ofbismuth, zinc, tin and combinations thereof, wherein said polyol premixcomposition has been stored for a period of at least several weeks andis sufficiently stable to form foams with no substantial collapse aftersaid period of storage.
 8. The polyol premix composition of claim 7wherein said non-amine catalyst comprises zinc 2-ethylhexanoate.
 9. Thepolyol premix composition of claim 8 wherein said non-amine catalyst ispresent in an amount of about 0.25 wt. % to about 3.0 wt. %, by weightof the composition.
 10. The polyol premix of claim 7 further comprisingan amine catalyst, provided said amine catalyst is present in an amountthat does not negate the foam forming ability of said polyol premixcomposition after said storage period.
 11. The polyol premix of claim 1wherein said blowing agent comprises from about 5 wt. % to about 90 wt %of trans-1-chloro-3,3,3-trifluoropropene.
 12. The polyol premix of claim7 wherein said blowing agent comprises from about 5 wt. % to about 90 wt% of trans-1-chloro-3,3,3-trifluoropropene.